The Phytocoenotic Potential of Pastures on the Sand Massifs of the Don Basin

Abstract: The phytocenotic potential of pasture ecosystems of the Tsimlyanskii sand massif using the ecological scales of humidity, soil reaction, and soil richness in mineral nitrogen of G. Ellenberg is studied. This work is based on landscape-bioecological and ecological-morphological research methods using methods for studying the structure, stability and development of plant communities. It has been established that the family types Poaceae, Fabaceae, and Asteraceaeplay the greatest role in projective coverage. The predominant life form of vegetation at all sites studied are is 40–71%. The average productivity of phytocenoses is 156–287 g/m². The species composition and productivity of pasture phytocenoses changes noticeably depending on the humidity, physicochemical properties, and the richness of the soil in mineral nitrogen. On moist, non-drying, slightly acidic soils with an average nitrogen content, edificators are Agrostis caninaL., A. tenuisSibth., Thlaspi arvenseL., Typha angustifoliaL., T. latifoliaL., Tanacetum vulgareL., Phragmites australis(Cav.) Trin. ex Steud., and Scirpus lacustrisL. Under average moisture conditions, on slightly acidic soils with an average nitrogen content, edificators are Achillea millefoliumL., Astragalus arenariusL., Elytrigia repens(L.) Nevski, Medicago falcataL., and Phleum pratenseL. Under average moisture conditions, on slightly acidic soils rich in mineral nitrogen, edificators are Apera spica-venti(L.) P.Beauv., Atriplex tataricaL., and Calamagrostis epigeios(L.) Roth. Under average moisture conditions, on neutral soils with an average nitrogen content, edificators are Artemisia abrotanumL., Cirsium incanum(SG Gmel.) Fisch., Gypsophila paniculataL., Inula germanicaL., Juncus gerardiiLoisel., and Senecio erucifoliusL.On dry, slightly acidic soils with an average nitrogen content, edificators are Chamaecytisus ruthenicus(Fisch. ex Wol) and Festuca valesiacaGaudin.On dry, slightly acidic and mineral nitrogen-poor soils, edificators are Anisantha tectorum(L.) Nevski, Artemisia campestrisL., A. maritimaL., A. marschallianaSpreng., A. scopariaWaldst. & Kit., Bromopsis inermis(Leyss.) Holub, Crepis tectorumL., Koeleria glauca(Spreng.) DC., Leymus racemosus(Lam.) Tzvelev, Potentilla incanaP. Gaertn., B. Mey. & Scherb., Psammophiliella muralis(L.) Ikonn., and Stipa capillataL. Under conditions of sufficient and variable moisture, on neutral and slightly acidic soils with an average nitrogen content, edificators are Agropyron cristatumL. and Thlaspi arvenseL. In the brome–bushgrass–wormwood (Bromopsis inermis, Calamagrostis epigeios, Artemisia marschalliana) community, there is a large proportion of therophytes (22.9%), which indicates anthropogenic pressure on this territory.